peptone, beef extract, yeast extract, sodium chloride peptone, beef extract, yeast extract, sodium chloride

yeast extract and peptone.

Yeast extract is used as a foodsource for growing bacterial and fungal cultures (and also for humans.) Yeast extract has most or all of the vitamins and minerals that cells need to grow and to multiply. For human comsumption, yeast extract is mixed with herbs and spices and used as a sandwich spread. 'Vegemite' is a popular brand of yeast extract in Australia.

why colony of agrobacterium is pink on yeast extract

The major ingredient for the foodstuff Marmite is yeast extract. The extract is a by-product of beer production. Similar products include Vegemite, Cenovis, and Vitam-R.